Writing instruments



2 Sheets-Sheet 1 Nov. 13, 1962 l. D. TEFFT WRITING INSTRUMENTS A Filed April 29, 1954v w3 %N\ ws NS s United States Patent O Filed Apr. 29, 1954, Ser. No. 426,355 6 Claims. (Cl. 1Z0-42.4)

The present invention relates to writing instruments.

The invention relates more particularly to capillary ball point pens.

A capillary pen, as the term is now known, is one having a reservoir of a capacity comparable to that of a conventional fountain pen in which the reservoir fills by capillary action when subjected to a supply of ink, holds the ink therein by capillary action and permits the ink to feed to the writing element by capillary action, in a writing operation. Such a pen utilizes thin, liquid ink. The preferred w-ay to fill such a pen is to immerse the forward end of the pen in the ink, but in the case of a ball point pen, the clearance between the writing ball and its socket, which must be small for effective Writing, is too small to permit effective filling therethrough. Filling through the rear end also has its disadvantages.

. An object, therefore, of the present invention is to provide a capillary ball point pen Which overcomes the above stated disadvantages and provides a novel Way of filling the pen.

Another and more specific object is to provide a pen of the foregoing character of novel construction including a filling passage to the reservoir in bypassing relation to the writing ball and seat.

A further object is to provide a pen of the foregoing character having a novel construction including a barrel or casing, and a writing unit having a writing ball, in whichV the writing unit has a filling opening normally concealed by the barrel, but the writing unit is movable for exposing the opening to the exterior of the barrel for filling purposes.

`Still another object is to provide a capillary ball point pen having a filling opening at its forward end normally concealed but exposable for filling purposes.

A `still further `object is to provide a pen of foregoing general character including a barrel and a writing unit having a filling opening adjacent its forward end normally concealed in the barrel, in which in one embodiment the writing unit is movable for exposing the filling opening forwardly of the barrel, and in another embodiment removable from the barrel for exposing the opening.

Another object is to provide a capillary ball point pen having novel filling means which is of extremely simple construction.

Other objects and advantages of the invention will be apparent upon reference to the following detail description taken in conjunction with the accompanying drawings in Which- FIGURE l is a longitudinal sectional view ofa pen embodying the principles of the present invention;

FIGURE 2 is a view similar to FIGURE l, but with the writing unit in elevation and in forwardly projected position;

FIGURE 3 is a large scale longitudinal sectional view of the forward portion of the pen of FIGURES 1 and 2;

FIGURE 4 is a large scale cross-sectional view taken on line 4-4 of FIGURE 3;

FIGURE 5 is a large scale sectional View taken on line 5 5 of FIGURE 3; and

FIGURE 6 is a longitudinal sectional view of a modified form of pen embodying the present invention.

The pen as noted above is of the capillary type, that is, it is capable of completely filling in response to the capillary reservoir element being subjected to a supply of ink. It is desired that the capillary 'reservoir element be ICC contained in a writing unit or cartridge which itself is contained in a barrel or holder. This arrangement facilitates filling the capillary reservoir element in that the writing unit or cartridge may `be more appropriately designed for containing the reservoir element and enabling filling thereof, and the barrel or holder may be designed simply for the purpose of containing the writing unit or cartridge and form a convenient article for holding in the hand.

Referring in detail to the drawings, and particularly to FIGURES l to 5 inclusive thereof, the pen or writing instrument shown in its entirety at 102 includes a barrel or casing 1014 having an open rear end normally closed by a removable cap 106. The barrel is of generally tubular shape having a relatively large bore or chamber 1112, forming a reservoir section, and a reduced diameter bore 114, forming a feed section, opening through the forward end of the barrel. A shoulder 122 is formed at the forward end of the reservoir section 112 surrounding the bore 114.

The writing unit 10S, to be described in detail later, includes a reservoir section 1.16 mounted in the reservoir section of the barrel, and a `feed section 116 in the form of a stern extending through the bore 114. The feed section mounts a writing ball I118 and is provided with a plurality of filling openings 119 adjacent its forward end rearwardly of the ball. A spring `120 surrounds the stem 116 and is compressed between the shoulder 122 and the forward end of the reservoir section of the Writing unit, to normally retain the unit in rearward retracted position (FIGURES l and 3).

The cap 106 closing the rear end of the barrel may be secured to the barrel by suitable means such as a screwthreaded connection and is provided with a longitudinal bore 124 which slidably receives the shank of a push button 126. At the forward end of the shank is a head 12S which engages the rear end of the writing unit 108 for moving the writing unit forwardly, as will be brought out later in detail, in response to forward movement of the push button by a manual actuation. The push button is provided with a vent opening for venting the writing unit 108, the rear end of which is open.y

The writing unit 108 includes a capillary reservoir element for storing ink and means for feeding ink from the reservoir element to the writing ball. The internal construction may be similar to that disclosed and claimed in the co-pending application of Ray A. Lawton, Serial No. 397,449, filed December l0, .1953, now Patent No. 2,847,- 975, issued August 19, 1958, to which reference is hereby made.

For convenience, a brief description of the internal construction of tbe-writing unit is Vgiven here. The writing unit 108 includes a casing 132, of suitable material, open at its rear end for venting the reservoir element contained therein. The reservoir element indicated generally at 134 is made up of a central main section 136 and two end sections 140. The central section 136 is preferably of the spiral wrap character disclosed and claimed in Bartell Patent No. 2,522,555, issued September 19, 1950, being made up of one or more thin sheets of material such as silver wrapped in spiral fashion providing a plurality of spaces 142 of capillary dimension, i.e., of such dimension and capillarity that the element is capable of lifting liquid ink to its full height When its lower end is immersed in a quantity of ink. The spiral space portions 142 are preferably interconnected by apertures which may be formed by punching or piercing the sheet, which operation also forms projections 144 for spacing the convolutions of the element apart. The end elements 140` may be of sponge material, for example, having pores of capillary size communicating with the spaces 142 and with the feed means leading to the writing ball, as will be explained in detail later. If desired, the rear end of the capillary element may terminate ush with the rear end of the casing 132, and the head 128 of the push button 126 engages the casing which receives the thrust from the push button. Preferably the forward end portion of the casing 132 is tapered slightly in a forward direction to prevent a wedging action with the tapered forward end portion of the reservoir section in the barrel.

The casing 132 of the writing unit has a forward end wall 146 which is provided with a central aperture and' a forwardly extending internally threaded tubular extension 148. The stem 116 includes a tubular element or sleeve 150 mounting the writing ball and containing the means for feeding ink from the reservoir element to the writing ball. This sleeve may be made of suitable material for forming a seat for the writing ball and resisting wear therefrom. The shank of the stem has a sliding fit in the bore 114 of the barrel, and at its forward end is an enlarged ball mount 151 having a suitable ball seat or socket 152 for receiving the writing ball. The rear surface of the ball mount is tapered at 153 for seating engagement with a complementally shaped surface 155 in the forward end of the barrel. The sleeve at its inner or rear end is threaded as at 154 for threading in the extension 148, and is dimensioned for enabling its insertion through the bore 114. The inner end of the sleeve forms an extension 156 projecting rearwardly into the central space 158 provided in the reservoir element and firmly engaging the latter, or at least the sponge element portion 138 thereof. A feed means 160 is fitted in the bore 157 of the sleeve 150. This feed means is of generally tricorn shape in cross section (FIGURES 4 and 5), and at its forward end has a reduced stem 162 extending into a reduced bore 164 leading to the ball seat 152. The rear or inner end of the sleeve 150i is cut olf on its sides at 166 (FIGURE providing side openings 168 to the bore of the sleeve and extending substantially the length of that portion 156 of the sleeve extending into the reservoir element. These side openings 168 communicate with the pores in the sponge element 138, as well as the apertures in the convolutions in the reservoir element 134. Ink feeds by capillary action from the reservoir element through the side openings 168 into the passages 170 between the surfaces of the feed element 160 and the inner surface of the sleeve. These passages lead forwardly to the bore 164 and then to the ball.

The apertures or filling openings 119 communicate directly with the passages 170 in the sleeve and are of greater than capillary dimension so that when the sleeve is immersed in a supply of ink, the hydrostatic head of the ink causes the ink to flow freely through the filling openings and into the passages 170, whereupon the ink rises by capillary action through the passages 170 and into the pores of the reservoir element 138 and then into the spaces 142.

The normal position of the writing unit is its rearmost position, as shown in FIGURES l and 3, being biased to that position by the spring 120. The surface 153` on the ball mount engages the surface 155 on the barrel, serving as a means for limiting the rearward movement of the writing unit. The writing unit and thus the writing ball assume a normally xed position. In this position the filling openings 119 are concealed in the bore 114 of the barrel, and the external appearance of the pen is a smooth over-all unbroken surface leading from the barrel to the ball mount 151.

When it is desired to ll the pen, the user merely depresses the push button 126 which forces the writing unit to the forward position of FIGURE 2 wherein the lling openings 119 are exposed to the exterior forwardly of the barrel. He may then insert the lower end of the pen into a supply of ink to an extent in which the level of the ink rises above at least some of the filling openings whereupon the ink passes through the openings and into the pen as above described. Upon releasing the push button 126 the spring 120 moves the writing unit in a supply of ink for filling purposes.

to its rearmost and normal position of FIGURES l and 3. If desired, the cap 106 may be provided with a Washer of resilient material on its inner surface against which the head 128 of the push button may abut, for eliminating undue play of the push button while enabling the ball mount 151 to seat or abut solidly against the forward end of the barrel. The washer 165 may =be secured to the inner surface of the cap 106 as by gluing, and may have a relatively large central aperture to avoid rubbing of the shank of the push button thereon.

The pen of FIGURE 6 represents a modified form of the invention and includes a barrel 171 quite similar to the barrel of the rst form of pen, this barrel having a chamber or reservoir section 172 from which a reduced diameter bore 173, forming a feed section, leads forwardly through the end of the pen. The rear of the barrel is closed by a cap 174 preferably secured to the barrel as by a screw-threaded connection and has a cavity 175 forming a continuation of the reservoir section 168. The rear end of the cap is vented at 176 for venting the rear end of the writing unit.

The writing unit 178 is similar to the writing unit 108 in all material respects but with certain minor changes. rIhe writing unit includes `a reservoir section 180 having a feed section 182 leading forwardly therefrom in the form of a stem and in the present instance the wall of the feed section may be made integral with the casing of the reservoir section. The forward end of the feed section 182 is provided with a plurality of filling openings 184 and the writing ball 186 is mounted in the extremity of the feed section which is of substantially uniform dimensions throughout, that is, it does not have an enlargment such as the ball mount in the first embodiment, the consideration being that the stem 182 may be withdrawn rearwardly from the bore 173.

The writing unit 178 is of appropriate length to extend into the cavity 174 of the cap, and its rear end and the cavity are complementally tapered in a rearward direction for frictionally securing the writing unit in the cap .for removal therewith from the barrel. This taper is relatively long so that substantial friction exists between the two elements whereby when the cap is removed the writing unit may be removed with it, and the latter held merely by holding the cap and the forward end of the unit inserted If desired, a resilient ring or washer 188 may be interposed between the rear end of the writing unit and the rear end of the Cavity in the cap to serve as a yielding stop means for the writing unit. However, the friction engagement between the writing unit and the cap is normally sufiicient to retain the writing unit in its normal intended position for writing, as shown in FIGURE 6. In this normal position it will =be noted that the tilling openings 184 are concealed in the barrel, and the external surface of the pen presents a smooth and unbroken appearance over the barrel and the projecting portion of the writing unit.

Each of the two forms provides an extremely simple construction enabling rapid and convenient filling of the pen.

I claim:

1. A writing instrument comprising a barrel including a tubular member having an open rear end and having a reservoir receiving section and a reduced dimension bore leading from the reservoir receiving section through its forward end, said forward end being the -gripping portion of said barrel, a cap removably closing the rear end, and a self-contained writing unit in the barrel including a reservoir section and a feed section extending through the forward end of the `barrel and removable rearwardly therethrough, the writing unit including a Writing ball in its forward end, a capillary reservoir element in its reservoir section and ink feed means leading from the reservoir section to the writing ball, said writing unit also having a filling opening adjacent the forward end of its feed seCtiOn but rearwardly of the writing ball in ink filling communication with the reservoir element, said cap having engagement with the writing unit and serving Ias rearward stop means for locating7 the writing unit in writing position therein wherein the writing ball is positioned forwardly of the barrel and the feed section and filling opening are completely concealed within and covered by said grippin'fy portion of the barrel, said feed section and filling opening being exposable to a filling position :by removing said unit from said barrel for imrnersing said ball and feed section and opening in ink.

2. A writing instrument comprising a tubular barrel having a reservoir-receiving section in its rear portion and a reduced dimension feed-receiving section at its forward end, said forward end -being the gripping portion of said barrel, a writing unit in the barrel having a casing and including a reservoir Section in the reservoir-receiving section of the barrel, a feed section extending through and guided by the feed-receiving section of the bar-rel and having a writing ball at its forward end, a capillary reservoir element in the reservoir section of the unit and ink feed means in the feed section `of the unit having capillary passages leading from the reservoir element to the writing ball, the casing of said writing unit having a filling opening in i-ts feed section adjacent to but rearwardly of the writing ball in direct ink filling communication with said capillary passages, and the writing unit having a normal position wherein the writing ball is closely adjacent the forward end of the 'barrel and the feed section and the filling opening of the casing are completely concealed in the feed-receiving section of the gripping portion of said barrel but movable to a position wherein the filling opening and the feed section of the unit are exposed to the exterior of the barrel.

3. The invention as set `forth in claim 2, wherein the writing unit is movable forwardly from its normal position to a forward position with the feed section and the filling opening exposed forwardly of the barrel.

4. The invention as set forth in claim 3, wherein means is provided for yieldingly biasing the writing unit rearwardly to its said normal position, and a push button iS provided for manually moving the writing unit to its forward position.

5. The invention as set forth in claim 2, wherein the writing unit includes a vent at its rear end andan enlarged ball mount at its forward end forwardly of the barrel; wherein spring means are provided that react between the forward end of the reservoir-receiving section of the lbarrel and the forward end of the reservoir section of the writing unit to yielding bias the writing unit rearwardly; and wherein a push button projects through the rear end of the barrel and engages the rear end of the writing unit to afford a manual actuating means for moving the writing unit forwardly.

6. A device of the character disclosed comprising: a writing unit including a casing having a forward writing end, a writing element mounted in said forward writing end, a capillary reservoir element in the casing capable of filling with ink by capillary action land retaining ink therein by capillary action until withdrawn by capillary action, said casing having a feed tube intermediate said writing element and said reservoir element forming a capillary ink feed passage connecting the reservoir element with the writing element, said casing having filling openings in said tube adjacent to and by-passing the writing element and communicating directly with said capillary ink feed passage, the casing -at least in its lforward portion being, except for the filling openings, imperfora-te to effective passage of ink thereinto, whereby the filling openings provide means enabling filling of the reservoir element upon immersion of the forward end of the feed tube in a quantity of ink; and a barrel for receiving said casing, the front end of said barrel being the gripping portion thereof, the casing being axially movable in the barrel from a writing position wherein said feed tube and said filling openings are completely covered by said front end-gripping portion of said barrel to a filling position wherein the forward part of said feed tube and all of said filling openings are exposed to the exterior of said barrel.

References Cited in the file of this patent UNITED STATES PATENTS 1,514,519 Harris Nov. 4, 1924 1,862,586 Vivian June 14, 1932 2,504,353 Rosa Apr. 18, 1950 2,522,554 Zodtner Sept. 19, 1950 2,603,186 Fischer July 15, 1952 FOREIGN PATENTS 944,811 France Nov. 15, 1948 498,040 Belgium Ian. 2, 1951 1,011,824 r.France Apr. 9, 1952 

